Prevalence and diagnostic value of precordial murmurs for valvular regurgitation in obese patients treated with dexfenfluramine

Echocardiography is recommended for the detection of valvular regurgitation in asymptomatic users of anorexigens with a heart murmur. To determine the prevalence and diagnostic value of heart murmurs for valvular regurgitatio n, 223 patients receiving dexfenfluramine therapy for 6.9 months and 189 ma tched controls underwent history and cardiac auscultation by experienced no ncardiologists unaware of echocardiography. Color Doppler echocardiograms w ere interpreted by 3 observers unaware of patients' clinical data. The freq uency of at least mild regurgitation of any valve and abnormal regurgitatio n (moderate mitral or tricuspid or mild aortic regurgitation) were determin ed. Heart murmurs heard in 31 dexfenfluramine users (14%) and in 20 control s (11%) were all systolic and of grade I to II/VI intensity. Mild or worse regurgitation of any valve showed a trend in patients (18% vs 11.6% in cont rols, odds ratio [OR] 1.66, confidence interval [CI] 0.95 to 2.9, p = 0.08) , but abnormal regurgitation (includes Food and Drug Adminstration grade re gurgitation) was more common in patients (9% vs 3% in controls, OR 3.0, CI 1.18 to 7.65, p = 0.02). In dexfenfluramine users, heart murmurs were assoc iated with at least mild or abnormal regurgitation (OR 3.1 and 3.05, 95% CI 1.34 to 7.13 and 1,1 to 8.67; p = 0.008 and 0.036, respectively), had a sp ecificity of 89% and 88%, negative predictive value of 85% and 93%, but sen sitivity of 37% and 30%, and positive predictive value of 35% and 19%, resp ectively. Most valves missed by cardiac auscultation had normal morphology and mild regurgitation. Finally, heart murmurs had better diagnostic value for either type of valvular regurgitation than heart murmurs and clinical v ariables or clinical variables alone. In summary, in dexfenfluramine users the prevalence of heart murmurs wets low and their absence predicted absenc e of mild or worse regurgitation of any valve or abnormal valvular regurgit ation. Therefore, cardiac auscultation should be the screening method of ch oice for detecting valvular regurgitation in users of anorexigens. (C) 2000 by Excerpta Medica, Inc.